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This Defense Intelligence Agency reference document, dated 10 March 2010, covers inertial electrostatic confinement (IEC) fusion. It was produced in FY 2009 under the DIA's Advanced Aerospace Weapon System Applications (AAWSA) program. The report focuses on work at the University of Illinois Urbana-Champaign and reviews IEC basics, experiments, theory and applications such as neutron sources, explosives detection and space propulsion. It concludes by proposing a breakeven experiment for p-11B fusion that uses a hydrogen plasma simulation.
“BEAMS”43 pages
UNCLASSIFIED/;Sf81il 8FFIIItliL ~81!! 8HLY plasma. When an ion beam is hot, the waves excited by the instability are ion acoustic type waves. Then one observes that a certain temperature ratio is required before the wave will go unstable. He also developed a two-dimensional perturbative (i5f) particle-in-cell algorithm to simulate the electrostatic interaction of electrons and ions in spherical inertial electrostatic confinement. i5f scheme is applied, because the noise level in i5f algorithm is significantly reduced, compared with conventional particle-in-cell simulation. Since a particle-in-cell simulation in two or three-dimensions is very computationally and memory intensive, it is necessary to seek computational methods and options which lead to solutions in a reasonable amount of time. A distributed computing approach is implemented by using parallel libraries. Applying a uniform grid spacing in spherical coordinates may lead to a stability problem due to singularity at the spherical center. In order to avoid the singularity issue, a two-dimensional rectangular domain and an immersed boundary method are applied so that a spherical domain inside the cathode gird of spherical electrostatic confinement is simulated by r-z coordinates. It is evident from the result that the growth rate of instability, a decreasing function of the longitudinal energy spread of ion distribution function, becomes reduced because the large energy spread induces strong Landau damping by parallel kinetic effects. Besides the effects of longitudinal Landau damping by the barn ions, a more monoenergetic beam is able to stabilize the instability because a growth rate of instability can be reduced for a higher beam density when the beam speed is fixed and located on the left hill in the diagram of growth rate versus beam speed. The growth rate does not change dramatically as a mode of angular perturbation increases. The results summarized in Figure 4.10 indicated that the two-stream instability is stabilized if the angular momentum spread of the beam ions is small enough, due to enhanced ion densification at the center of the device. This is very encouraging for future IEC development. However, an experimental study should be performed to verify this result. RIDER - ENERGY BALANCE STUDY Todd Rider in Reference 4. 7 reports a quite different type of energy balance analysis. While the prior papers used various methods to concentrate on up-down scattering in various potential well configurations, Rider considered a "block diagram" type energy flow balance to determine the net gain from a power unit. In such an analysis the reaction and scattering rates, plus the electron-ion equilibration rates, enter as () averaged over the distribution functions for ions and electrons. Thus, the distribution functions were not calculated explicitly in Rider's analysis. In addition to the base function, any spatial variations in the distribution, such as pointed out by Tzonev et al., must be envisioned via the assumed distribution function. In traditional magnetic confinement analyses a Maxwellian distribution function has generally been assumed. In prior Tokamak studies, this technique has been widely used with reasonable accuracy since such systems are indeed near thermal equilibrium. In sharp contrast, as stressed repeatedly here, the IEC is not. This uncertainly in makes an analysis of the type attempted by Rider very challenging, and leaves it open for possible criticism. In fact, it appears that Rider used Maxwellian key averages and critics generally cite this as the cause for his pessimistic 43 UNCLASSIFIED/,'f81il 8ffll1Als WliEii &••blf
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Report, from the dia collection. The PDF is mirrored here; the original link is under it. 72 pages are in the text index: search them above, or from the library's search.